1. Field of the Invention
This invention relates generally to occupant restraint systems for motor vehicles and, more particularly, to a blow molded airbag with fabric reinforcements.
2. Description of Related Art
With the advent of more stringent vehicle safety standards promulgated by governmental agencies, advanced occupant restraint systems for motor vehicles are being developed by the vehicle manufacturers. More specifically, technology currently exists for occupant restraint systems that include cushioning devices commonly referred to as "airbags". These systems are designed to deploy an airbag from a folded inoperative position into an inflated operative position in order to cushion the vehicle operator and passenger in the event of a collision. Upon inflation, the airbag intervenes between the vehicle occupants and structural components such as the windshield, instrument panel, and steering wheel. The shock and impact that would otherwise be totally imparted to the vehicle occupants as a result of the collision condition can thus be absorbed or dampened by inflation of the airbag.
Generally, such systems include a pressure fluid source of any conventional type, such as stored gas, gas generating or a hybrid thereof. The source may be mounted on the steering wheel or the steering column, or may be mounted remote from either and connected for communication with the inflatable airbag. Sensors which actuate the pressure fluid source are normally mounted remote from the vehicle cabin in order to instantaneously sense any impact received by the vehicle or the probability or possibility of such impact upon rapid deceleration.
Conventionally, the airbag is located in a recess in a central portion of the steering wheel and is held in its inoperative "deflated" state by a cover member. Numerous concepts are known in the industry for permitting the cover member to break away or rupture during inflation of the airbag. Likewise, airbag restraint systems are available which are designed to protect vehicle passengers other than the driver from injury during a collision. Such systems are generally provided in the dashboard structure directly facing a front seat passenger. Again, numerous systems are now known in the automotive industry in this regard.
Airbag restraint systems, while proven to be effective, are extremely expensive. Motor vehicle manufacturers have been reluctant to install airbag restraint systems because the expense must be normally passed on to the consumer. Presently, the majority of airbags installed in motor vehicles are fabricated from a multi-piece fabric material and are very expensive to manufacture. Typically, the fabric airbags include upper and lower circular walls of a coated fabric material which are secured together (i.e. sewn) at their common peripheral edge.
3. Summary of the Invention
Briefly stated, the present invention is an improvement over conventional passenger restraint systems employing fabric airbags. The present invention encompasses application of blow molded plastic airbags which have fabric reinforements encapsulated thereon. Blow molded airbags can be fabricated for a fraction of the cost associated with conventional fabric airbags. Moreover, the reinforced plastic airbags are a direct alternative to conventional fabric bags. As such, the plastic airbags may be disposed within a steering wheel restraint system to protect the driver and, likewise, may be mounted within the vehicle dashboard to protect a passenger.
The improved airbag comprises a one-piece blow molded thermoplastic airbag having at least one fabric reinforcement insert encapsulated on a localized area thereof to provide supplemental structural support upon inflation. Additionally, the present invention includes a blow molded airbag which is tethered for controlled inflation. A fabric reinforcement pad encapsulated on the airbag and to which tethers are mounted permits an improved deployment pattern which "surrounds" the occupant. In this manner, the occupant is inhibited from "bouncing-off" the airbag which is a concern associated with conventional fabric airbag restraint systems.
Accordingly, it is an object of the present invention i to provide a one-piece blow molded airbag which can be readily integrated into existing occupant restraint systems as a design alternative to conventional coated fabric airbags.
Another object of the present invention is to provide a new and improved blow molded airbag having at least one reinforced fabric insert encapsulated at a preselected position to provide supplemental structural integrity to the airbag upon inflation.
It is still another object of the present invention to provide an airbag which is simple in construction and which is suitable for installation in the limited space of motor vehicles. The improved airbag is a simple one-piece blow molded structure which can be economically manufactured in a commercial production environment.
Other objects, features and advantages of the present invention will become apparent from the subsequent description and the appended claims taken in conjunction with the accompanying drawings.